What is CALLBACK? How it work?
what is the advantage of CALLBACK,
please explain with an example

Answer Posted / zero zero....

• callback function is a function that is called
through a function pointer.
• pass the pointer (address) of a function as an
argument to another, when that pointer is used to call the
function it points to it is said that a call back is made.
// 2.1 define a function pointer and initialize to NULL
int (*pt2Function)(float, char, char) =
NULL; // C
int (TMyClass::*pt2Member)(float, char, char) =
NULL; // C++
int (TMyClass::*pt2ConstMember)(float, char, char) const =
NULL; // C++

• A callback function is a function that is passed
to another function (in the form of a pointer to the
callback function) so that the second function can
call it. This is simply of way of making the second
function more flexible without the second function needing
to know a lot of stuff

Uses:
• A callback can be used for notifications
• callback functions can be used for updates, sort of
like hooking into another function. For example, consider a
function that downloads files using http. Your application
may want to display progress to the user. You could pass a
callback function (display progress) into the download
function so that it calls your display function everytime
it reads from the socket. At least that is my
understanding...

Is This Answer Correct ?    30 Yes 6 No



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